Pipe wrench



May l2, 1931- T. F. cuNNiNGHAM ET AL '1,805,078

PIPE WRENCH Filed July 18, 1929- F3-fl' I v? ga j l 1114@ AT-ro Nays d."o ment.

`Patented May `12,1931

'UNITED STATES.

THOMAS F. CUNMNGHAM AND'ARTHUR n. eieren-n, or BooN'roN, NEW'JERSEY iPIPE Vwennen Application filedy July 18,k

The pipe wrench of the present invention, while capable of generalutility is ymore especially intended for use in connection withrelatively large pipes, say from four inches to two feet and upwards indiameter.

An object'of the invention is to provide a wrench which issubstantiallyproof against slipping or twisting when in use and which thereby servesto effectively apply the desired turning force always at right angles tothe pipe. I

Another object is to' provide a wrench of rugged, durable constructioncapable ofuse on a widely varying range of pipe sizes, and

one which, while assuring full power transmission to the pipe, iseffective to minimize injury to the pipeeven when maximum pressures areexerted.

Another object is to provide a wrench having an effective downstrokefaction and, therefore, particularly applicablegto work on over-headpipes or pipes located in comparatively inaccessible places. Oneimportant result obtained by the' downstroke action 5 is that the weightof the handle is always opposing the torque resistance of the pipe,

whereas with an upstroke handle the weight of the handle and the torqueresistance are cumulative forces which the operator must overcome. s' nAnother object is to provide a wrench so l designed that the slightestreverse pressure on the handle willA disengage the wrench from the pipe,so that moving the wrench l y 1 Y 3" from one gripping position toanother 1s accomplished with a minimum ofv effort. rThe wrench is quickto engage the work as the handle is moved one way and equally quick torelease it upon retrograde handlemove- In a preferred embodiment of theinvention the wrench is of the'type employing a contractile, articulatedpipe i encircling in'einber,'such as aV chain, but contrary to prior l-practice both the shoe of the wrench handle and the anchor link'of thechain are toothed or serrated to cooperatively grip the pipe in apowerfulmanner whichentirely obv-iates the danger of slippage. There isthus pro'- vided a wrench havingone or Anrorefpairs of connection withthe accompanying drawings, wherein:

' line of Fig. 2, and,

' much smaller diameter.,

Vtively heavy bar stock, tapering in width may serial No. 379,094.

pipe gripping or biting elements engagingin circumferentially spacedsections of `the pipe surface and acting together to twist the pipe andprevent slipping of the tool as the torque is applied to the work.' e

Preferably also both the toothed anchor linky of the chain, and the pipeengaging shoe are readily reversible to-bring unworn surfaces into playwhereby a double life is insured for both of these elements.

In a preferred construction the shoe consists of a pair of paralleltoothed disks, with a spacer unitary therewith thus affording a grooveto straddle the lower edge of the handle which may be connected in placeby a bolt. lThe bolt may-be selectively passed through either of twopairs of diametrically aligned openings` in Vthe shoe whereby the shoeisreversible. The anchor link of the chain is of arcuate form, havingopenings at its ends .for pivotal engagement with the ends of the shoebolt and with an adjacent chain link respectively. Since the openings atboth ends of the anchor link areidentical` this link may also bereversed when one end 7* thereof becomes worn. i The invention may bemore fully under! stoodv from the following description in Fig. l is aplan view of our improved wrench showing the same in operative relationto a.l pipe, f y

Fig. 2 is a side elevational view thereof with the pipe in section, i j

Fig. 3 is a vertical'sect-ional detail on the Fig. 4 isa view similartoFig. 2, but showing the wrench applied to a pipe of m In the drawings wehave used the reference numeral l0 to designatek the handleof the wrenchwhich maybe vof flat and'relatoward its free end and being of slightlyre- 9" duced thickness .at 10a adjacent it-slwidelr working end. l. f

The shoe or fulcrum member whichis fixed upon vthe end ofthe handlemay'conf veniently include a pair ofrelatively heavy Cil disks 11 spacedapart a distance equal to the thickness of thehandle portion 10 andrigidly connected together by a central web block 12 of elongatedformation having flat sides and having its axis disposed along one ofthe diametric axes of the disk. Preferably as shown in Fig. 3, the disks11 and the block 12 are a unitary forging or casting or are Weldedtogether of originally separate pieces. Pairs of aligned openings 18 and14: are provided in the disks between the disk edges and the web block,these openings being preferably arranged upon acommon diametric axis at`right angles to the axis of the web block. When Vthe disks whichconstitute the shoe are positioned to straddle the lower edge of thehandle lever, and one of the fiat sides of the web block abuts the loweredge of the lever, one of the other pair of openings 13, 14 may bealigned with a corresponding opening 15 in the wrench handle and thelshoe may be secured in place by a bolt 16 passed through the alignedopenings 13, 15 or 14, 15 as the case may be.

The articulated pipe embracing member may be a chain of more or lessconventional construction, each link as best seen in Fig. 1 comprising apair of spaced parallel plates 18 connected to the straddled orstraddling plates of an adjacent link by a common pivot pin 19. Theanehorlink of this chain, however, is of special formation comprisingrelative long massive arcuate plates Q0, the concave edges of which aretoothed or serrated at 21. The plates of the anchor link are connectedby a pivot pin 19u to the adjacent link 17 of the chain, spacer membersbeing provided if necessary to compensate for the distance between theplates of the anchor link since the latter preferably straddle the shoe11, 12 and their ends are pivoted on the projecting ends of the bolt 1G.

In operation the free end of the chain is wrapped around the pipe 30 andone of the chain links is engaged with an upstainling lug 23 on the topof the lever end. 'lhus with the parts in Fig. 2 the normal gravityaction of the lever will cause the lever and shoe to rock about thepoint of'centact between shoe and pipe as a fulcrum in which movementthe lug Z3 is drawn in a direction to tighten the chain 17 about thepipe and pull the anchor lilik 20, 20 into iirm engagement with thepipe. In other wort s, with the tool in the position of Fig. 2 theweight of the lever causes the tool to firmly grip the pipe and theweight of the lever is effectively applied in a direction to oppose thetorque resistance of the pipe. As the free end of the lever is grasped`and manually pulled down the pipe is caused to turn since the lug 23being more remote from the fulcrum point 25 than the bolt 1G, swingsthrough a greater arc with resultant tendency to tighten the chain andthrough it apply a twisting move-- ment to the pipe.

As the lever is lifted up lever and shoe again rock as a unit about thefulcrum Z5 and in this rocking motion movement of the lug 23 is througha longer path than .pivot 16, causing slack in the chain andinstantaneous release of the pipe 30.

Thus the lever may be oscillated back and forth with substantially nolost motion at the start of its working stroke and with no specialeliort needed to cause release at the start of the idle stroke otherthan the power required to lift the weight of the lever itself.

lVhen wear occurs on the teeth of the disks 11 or on the anchor links ofthe chain these elements Vmay be -conveniently reversed to bring newunworn teeth into engagement with the surface of the pipe. Reversal ofthe shoe is accomplished by merely removing the bolt 16 and invertingand replacing the shoe. Reversal of the link plates 2() is accomplishedby removing both the bolt 16 and pivot pin 19 and then reconnectingthese plates to the shoe and chain respectively with their ends inreversed position, that is to say, with the ends that have beenpreviously attached to the bolt new connected to the pivot pin.

Figure l requires no special description, but is illustrative in aself-evident manner of the fact that the wrench is applicableconveniently to a large range of pipe sizes, it being here shown appliedto pipe CL of much smaller diameter than the pipe 30.

Due to the four-point biting or gripping Contact, a wrench constructedin accordance with the present invention cannot slip or turn sidewiseand always exerts its pressure at right angles. The pressure of thewrench is well distributed reducing` the scarring of the pipe when amaximum pressure is exerted. rllhe circular design of the shoe reducesmanufacturing costs both in casting and finishing. permits the wrench toengage the work at any point on the circumference of the shoe andpermits reversibility discussed above. The wrench is readily adaptableto a large size range of pipes and is comparatively light in weight.

lt will thus be vseen that there is herein described apparatus vin whichthe several. features of this invention are embodied, and whichapparatus in its action attains the various objects of theinvention andiswell suited to meet the requirements of practical use.

is many changes could be made in the above construction, and manyapparently widely different embodiments of this invention couldvbe madewithout departing from the scope thereof, it is intendedthat all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a vlimiting' sense.

Having thus described our invention, what We claim asnew and desire tosecure by Letters Patent of the United States is l. In a pipe Wrench, ahandle lever, a shoe fixed to the end of the lever and adapted toprovide a fulcrum at its point of engagement with a pipe, an articulatedflexible device to encircle the pipe, pivotally connected at one endtothe lever, a member on the handle to be selectively engaged withone ofthe free links of the articulated device, said member being fixed on thehandle at a greater distance from the fulcrum point than the distance ofthe pivot from the fulcrum point, the shoe comprising a pair of spaced 1disks to straddle the lever and movable to present different fulcrumsurfaces to a pipe, a web block rigidly connecting the disks andincluding a flattened portion to lie against the edge of the lever.

2. A pipe Wrench including' a handle lever, a fulcrum shoe fixed at theend of the lever, the shoe comprising a pair of rigidly connected spaceddisks lying on opposite sides of the lever and movable to present diff.ferent fulcrum surfaces to a pipe, a chain pivoted at one end to thelever, and an anchor lug on the lever to detachably engage any free linkofthe chain after the chain has been passed around a pipe.

3. A pipe wrench including a handle lever, a fulcrum shoe fixed at theend of the lever, the shoe comprising a pair of rigidly connected spaceddisks lying on opposite sides of the lever and movable to presentdifferent fulcrum surfaces to a pipe, a chain pivoted at one end tothe-lever, and an anchor lug on the lever to detachably engage any freelink of the chain after the chain has been passed around a pipe, themeans for rigidly connecting the disks of the fulcrum shoe comprising anintegral elongatedv web block, the axis'ofl which is coincident with oneof the diametric axes of the disks, said block providing flat sides forengagement with an edge of the lever.

4. A pipe Wrench including a handle lever, a fulcrum shoe fixed at theend of the lever, the shoe comprising a pair of rigidly connected spaceddisks lying on oppositesides of the lever and bolted thereto, a chainpivoted at one end to the lever, and an anchor lug on the lever todetachably engage any free link of the chain after the chain has beenpassed around a pipe, the means for rigidly connecting the disks of thefulcrum shoe comprising an integral elongated web block,

the axis of Which is coincident with one of the diametric axes of the,disks, said block providing flat sides for engagement with an edge ofthe lever, the disks having pairs l of aligned openings therein arrangedat opposite sides of the web block and on a com# mon diametri@ axis atAright angles to the axis of the Web block. y f

5. A pipe Wrench including a handle lever,

free-link of the chain after the chain has been passed around a pipe,the anchor link of the chain comprising a pair of plates of arcuate formserrated along their concave edges for biting engagement With the pipe'and With their ends pivoted on the ends of the shoe bolt, the length ofsaid plates being considerably in excess of the radius of the disks.

6. In a pipe Wrench a handle lever and shoe fixed to the end of thelever and adapted to provide a fulcrum at its point of engagement with apipe and articulated flexible device to encircle the pipe, pivotallyconnected at one end of the lever,.means associated With the handle tobe selectively engaged With one ofthe free links of the articulateddevice, said shoe and one of the links of the articulated device beingserrated to provide spaced pipe gripping members.

7. A Wrench as set forth in claim 6 and wherein the serrated link is thelink Which is permanently connected to the lever, said link being ofgreater length than the remaining links of the flexible device.

8. In a pipe wrench a handle and a pipe encircling flexible deviceassociated with the handle and adapted to tighten about the pipe as thehandle is moved in one direction and spaced pipe engaging and grippingelements associated With the handle and the flexible devicerespectively, one of said elements comprising a fulcrum shoe lixed tothe handle, the other of said elements comprising a swinging arm pivotedto the fulcrum shoe.

9. In a pipe Wrench a handle and flexibledevice to encircle the pipesaid flexible device being contractible as the 'handle is moved in onedirection, a pair of spaced pipe gripping elements movable to presentdifferent fulcrum surfaces to a pipe andmeans whereby said elements arecaused to firmly engage the pipe as the handle is moved to tighten theflexible device, one of said elements compris ing an'arcuate armpivotally connected to the i handle at one end and the chainl at itsother end.

Signed at Boonton, in the county of Morris and State 'of New Jersey,this 15th day of July, 1929.

' THOS. F. CUNNINGHAM. v ARTHUR vI-I. GIFFORI).

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